Application of FeIII-TAML/H2O2 system for treatment of fluoroquinolone antibiotics

Over the recent past, fluoroquinolone antibiotics (FQs) have raised extensive attention due to their potential to induce the formation of resistance genes and superbugs, thus various advanced oxidation techniques have been developed to eliminate their release into the environment. In the present study, the prototype tetraamido macrocyclic ligand (Fe-III-TAML)/hydrogen peroxide (H2O2) system is employed to degrade FQs (i.e., norfloxacin and ciprofloxacin) over a wide pH range (i.e., pH 6-10), and the reaction rate increases with the increase in pH level. The effect of dosage of Fe-III-TAML and H2O2 on the degradation of FQs is evaluated, and the reaction rate is linearly correlated with the added amount of chemicals. Moreover, the impact of natural organic matters (NOM) on the removal of FQs is investigated, and the degradation kinetics show that both NOM type and experimental concentration exhibit negligible influence on the oxidative degradation of selected antibiotics. Based on the results of liquid chromatography-high resolution mass spectrometry and theoretical calculations, the reaction sites and pathways of FQs by Fe-III-TAML/H2O2 system are further predicted and elucidated. (C) 2020 The Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences. Published by Elsevier B.V.

Automated summary

This study demonstrates that the Fe-III-TAML/H2O2 system can effectively degrade FQs antibiotics, with the reaction rate increasing with higher pH levels and showing linear correlation with the added chemicals. The presence of natural organic matters has negligible impact on the removal of FQs, and the kinetics of oxidative degradation of the selected antibiotics are minimally influenced by NOM type and experimental concentration.